Start with the simplest variation you can, adding embellishments over each round of iteration.
Learn the underlying basics like string skip relationships to develop better fingering and phrasing allowing you to execute with fluency.
Elangathu Veesuthe Raga and Scale
C D Eb F G A Bb notes are used to play the song, implying the C Dorian scale. The practical guitar player needs to know the string/frets used and not used to play without doubt. That is the scale information.
Depending on the slide rules added to the notes, a raga name can be given. Since Raga Kharaharapriya is the equivalent of Dorian, the raga for the song could be a janya or derivative of Raga Kharaharapriya.